WALTHAM, Mass. -- A few ticks after 2 o'clock, the official start of the Boston Celtics' media day event on Monday, president of basketball operations Danny Ainge and Rajon Rondo plopped down at a podium in front of an overflow throng of reporters. Ainge playfully joked to Rondo that he could have at least tucked in his jersey, to which the All-Star point guard cracked back that it was an impossible feat given that his left arm was immobilized by an oversized black sling.

And with that, Rondo calmly -- and often playfully -- attempted to defuse any concerns about the cause of a left hand injury that required surgery on Friday and will sideline him for the start of the 2014-15 season.

Rondo confirmed an ESPN report that he told team officials he slipped in the shower, leading to a fracture. When pressed for specifics, Ainge asked a reporter, "Are you an investigator?" Rondo himself would soon joke, "Am I under investigation?"

Rondo complied, though, and laid out a detailed timeline of events from last week, one that included two trips to local trampoline parks with his kids, along with a humorous aside about his exploits in a Celtics team softball game. ("I made a couple top-10 catches and a one-handed grab, throw-out at first base that was really good; I impressed myself with that," Rondo said.)

It may do little to sway a skeptical public, but Rondo's bosses seem OK with his story. Ainge went so far as to detail how he slipped in a shower in Las Vegas this past summer and ended up staying overnight in a local emergency room while being patched up.

Asked if the team planned to pursue the incident any further, Ainge offered, "No, we're not investigators."

Rondo said he's trying to stay positive in the face of another setback, this after missing much of the past two seasons because of an ACL tear. Both he and Ainge stressed that Rondo is motivated to reestablish himself -- and the Celtics franchise -- among the league's elite.

"A lot of people are doubting me and doubting this team," Rondo said. "I've always enjoyed being the underdog. What people say really doesn't matter to me. I have a lot of expectations for myself. I'm pretty sure I'm the hardest critic on myself, so I'll go out there and do what I do best and play the game."

Ainge echoed those sentiments.

"A lot of people will think he's motivated because he's a free agent [next summer]," Ainge said. "I don't think that's what drives Rajon. I think that he's motivated because he didn't play to his standards coming off the knee injury. He doesn't like to not be good. He doesn't like not being considered one of the best point guards in the game. I think that's what drives him, that's what motivates him, and that's what drove him to hard work this summer."

There's a sense of disappointment in the organization, not from the events leading to Rondo's injury, but merely that he won't be available to the team for as many as 10 weeks. Make no mistake, the Celtics know full well they remain in rebuilding mode and even Rondo admitted as much Monday. "I know this isn't a championship team, but we're going to go out there every night and fight hard," he said.

The Celtics won 25 games last season in coach Brad Stevens' first year at the helm, but are hoping to take the next step in their rebuilding process this season. The length of that stride could depend largely on Rondo's health and ability to elevate his younger teammates.

All of this is set against a bigger picture, which is Rondo's uncertain future in Boston.

The 28-year-old point guard will be an unrestricted free agent next summer and has expressed a desire to test the open market. While Ainge has admitted he can't unequivocally dismiss the potential that the team would consider trading Rondo this year, he also has maintained that both the team and Rondo desire a long-term future together.

Rondo, who hasn't talked to reporters since June, was asked if he wants to stay in Boston beyond this season. He replied with an emphatic "yes."

He added, "The fans, the people here make me want to stay. The organization has been great. I can't say enough about Danny and [team owner] Wyc [Grousbeck]. When I walk down the street, the fans embraced me from Day 1.

"Even when we won a championship, people don't just appreciate us winning. It's more of a 'thank you.' It's a love for the game. These people here know the game and they care for it. They know when you're BS-ing them around and you're not playing as hard as you can.

"The love you get is kind of overwhelming in Boston. Why wouldn't I want to stay here?"

And those pesky trade rumors?

"I think each year, my name gets bigger and bigger in trade rumors," Rondo said. "Danny keeps a pretty good communication line open with me, as far as everything that's going on. The reports may come out here and there, but I'm pretty focused on just living my life during the summer. I don't watch any TV at all.

"I haven't talked to you guys in a while. The reports come out, as long as Danny is talking to me -- he picks up his phone all the time and he's straightforward with me -- I'm fine with the rumors. They've been something my entire career."

Rondo smiled and glanced toward Ainge before adding, "It may be something I negotiate -- a no-trade clause or something like that to keep my name out of the trade rumors. That's part of it. No big deal. It's not only me that's in the trade rumors, but I am in it every year. It's part of it."

With a focus on that future, Rondo was asked if he sees himself as a maximum-contract player. He hesitated momentarily while seemingly pondering whether to answer the question, then smiled and said, "Yes, I do," while Ainge playfully winced a bit next to him.

After Rondo bounded off for the next station in his media day tour, Ainge was asked whether he sees Rondo as a max player.

"I think a four-time All-Star by the time he's [28] years old would qualify for max based on what we've seen in the marketplace," Ainge said. "If I were Rajon and I were Rajon's agent, I would definitely say that. But since I'm negotiating against him, I'll withhold."

As this latest episode confirms, Ainge has put a lot of faith in Rondo and has steadfastly stood in his corner. There's an eagerness to see what's possible with a healthy Rondo leading the team, but it's been stalled by his recent injury. Rondo is going to dominate the headlines for the Celtics this season and Ainge is hoping they'll soon focus more on what he's doing on the court than off.